Performance of a Azimuthally excited 3D-printed resonator for multi-pass spectroscopic applications

Abstract

Abstract-A design is presented for an acoustically resonant cell, based on the excitation of azimuthal resonances, to enhance the sensitivity of multi-pass photoacoustic spectroscopy. The acoustic cell is fabricated in one part using a photo-polymerization based 3D-Printing technique. Characterization of the cell performance is undertaken using calibrated concentrations of methane. The quality factor (< 76) of the cell compares favorably to existing designs based on longitudinal resonances. The minimum detectable normalized noise equivalent absorption coefficient for the cell was measured as: 3.667×10 -10 Wcm -1 Hz -1/2 , resulting in a minimum sensitivity for methane of 6 ppm with 700 s of averaging.